Damage analysis of stress corrosion test of pretensioning steel strands by ae monitoring

Abstract

In the present work the application of acoustic emission technique has been proposed as a tool for the
evaluation of corrosion processes occurring under SCC conditions on prestressing steel strands. To simulate
the possible corrosive environment under service conditions experimental tests were performed with different
electrolytes and electrochemical conditions (open circuit potential, cathodic and anodic polarisation). The use
of multi-variable techniques, coupled to a classic statistical approach, has permitted to discriminate separated
clusters in the population of the acquired AE signals related with specific damage events. Thereby the
proposed approach allowed to create corrosion maps able to classify both global and punctual degradation
phenomena. In particular different areas of the maps were related to the different corrosion mechanisms
experimentally observed during the SCC tests.